A switch device having a jog dial is known as a switch device. The jog dial is generally a cylindrical operation member and is mounted to be rotationally operated. The jog dial can be used to indicate directions, e.g., used as an up cursor key or a down cursor key, hence is considerably excellent in operability. The switch device having the jog dial is for example disclosed in Japanese Publication No. 2002-91694.
For example, it is considered to mount such a jog dial to a steering wheel of a vehicle as an input device or an operation device for a car navigation system. In this case, a display of the navigation system is for example arranged close to a speed meter within an instrument panel. In this construction, the jog dial is arranged such that a rotation axis extends horizontally. When the jog dial is rotationally moved in the upward direction, the jog dial is used as the up cursor key. When the jog dial is rotationally moved in the downward direction, the jog dial is used as the down cursor key.
For example, when plural selecting items are listed in the vertical direction in the display, an item of the plural selecting items can be selected by rotationally moving and operating the jog dial in the upward direction or the downward direction. As such, the selecting items can be easily selected.
However, when a user (driver) rotates the steering wheel, an operation direction of the jog dial is inclined relative to the vertical direction, i.e., the arrangement direction of the selecting items. Accordingly, the driver is likely to feel physical disorder to select the item from the plural selecting items, which are vertically arranged. In particular, when the steering wheel is rotated 90 degrees or more from a basic position, the operating direction of the jog dial is largely inclined or opposed relative to the vertical direction. Therefore, the driver is likely to feel physical disorder, and operability of the jog dial reduces.